Patient treatment in the medical arts often requires endotracheal intubation. Direct visualization of the larynx using a rigid laryngoscope constitutes the primary means of achieving endotracheal intubation and is called direct laryngoscopy. Integral to successful cannulation of the trachea is proper patient positioning. Frequently, this practice is overlooked by novice intubators. Even more important, proper patient positioning in the emergency setting is neglected or even dispensed with altogether due to the inherent time constraints related to emergent endotracheal intubation. Indeed, improper patient positioning is the most frequent cause of failed intubation in the difficult airway (defined as the inability to place an endotracheal tube on three attempts or within ten minutes). Manual attempts to obviate poor laryngeal view by manipulating patient position are nonstandard, unreliable and extremely time inefficient.
In the emergency setting, it is estimated that 99% of intubation attempts will ultimately be successful while in the operating room the failed intubation rate is only thought to be 5 to 35 per 10,000. Nevertheless, a difficult or failed intubation can result in death, brain injury, airway trauma, tracheal or esophageal perforation, pneumothorax and aspiration. Although direct laryngoscopy has been practiced for nearly a century, it was not until the 1990's that management of the “difficult airway” received serious attention. In recent years, there has been an attenuated need for invasive procedures like the cricothyrotomy with the advent of better training and the development of various airway adjuncts like the Combitube, Laryngeal Mask Airway (LMA), the Trachlite and Eschmann stylet (gum elastic bougie). Although a multitude of these airway management devices and “rescue” products are now available, methods other than direct laryngoscopy are seldom employed. In fact, proper patient positioning remains the primary means of achieving endotracheal intubation when laryngeal exposure is limited.
Successful endotracheal intubation using direct laryngoscopy is contingent upon alignment of the oral, pharyngeal and laryngeal axes in what is called the “sniffing position.” In this position, the patient's head is slightly extended and the occiput is elevated approximately 7 cm. Often, positioning the patient in this manner is enough to obtain a reasonable POGO (percentage of glottic opening) score that allows identification of the usual laryngeal landmarks.
However, laryngeal exposure can be limited due to a multiplicity of factors. Distortion (trauma, infection, neoplasm, edema etc.), disproportion (tongue/pharynx) or body habitus (particularly obese patients), can all compromise landmark recognition and make the sniffing position suboptimal or even inadequate. The laryngoscopist can sometimes compensate for limited laryngeal exposure by lifting the patient's head off of the bed with the laryngoscope. The human head weighs 8 to 10 lbs. and, in obese patients, such lifting of the head and shoulders may be impossible. However, the medical literature has shown that laryngeal exposure can be improved with less required force by increasing head elevation and neck flexion. Without a mechanical device to enable this, massive amounts of support must be placed under the head and shoulders. To date, virtually no equipment has been developed to optimize patient head positioning when the difficult airway is encountered.
In order to achieve proper body positioning for endotracheal intubations, body support devices have been created. For example, U.S. Pat. No. 4,259,757 issued to Watson entitled “Support Cushion” discloses a cushion for medical use to support a patient's head and neck that can be utilized to achieve the sniffing position of the patient's head and torso to facilitate endotracheal intubations. However, the cushion is for support of the head only and cannot provide any support for the patient's shoulders or torso which is desired for a full support system to achieve the sniffing position of the patient. U.S. Pat. No. 5,048,136 discloses an infant support for airway management which aligns the oropharyngeal, laryngeal and tracheal axes of an infant. This support is in the form of a cushion with cut-outs which receive the head and torso of the infant. However, this mat is not adjustable in any way. Adjustable head and torso supports are known for example as shown in U.S. Pat. No. 5,528,783 issued to Kunz et al. This patent discloses an inflatable head and torso support which is adjustable by the user whereby an air bladder can be fully inflated, partially inflated, or fully deflated as desired by the user to incline the head or the head and torso. Inflation is controlled by valves that are in turn actuated by switches located on the edge of a sheet of material positioned under the torso of the user and attached to the support. The support is wedge-shaped and contains only one bladder. Therefore, it is incapable of individually elevating the head and torso portions of the user's body independently and therefore would not be appropriate as an ideal tracheal intubation body positioning support.
There is therefore a need in the art for a patient positioning system that allows the patient's body position to be changed and controlled as needed in order to achieve the best possible position for endotracheal intubation.